Hardware and "How to..."

FT4 via satellite with SDR-Console and IC-705 / IC-9700

This is a simple guide for working FT4 mode via satellite with the help of SDR-Console software, a SDR receiver and Icom IC-705 as transmitter. The IC-705 can of course be replaced by any other radio that can be controlled via OmniRig.

I have also tested this with an ICOM IC-9700 with equal good result.

The “magic” is done by Omnirig. This smart little software can connect several software to one radio at the same time, in this case SDR-Console and WSJT-X.

This guide requires that you have basic knowledge of the following:

  • WSJT-X and FT4 operation
  • SDR-Console V3 satellite operation
  • IC-705 operation (or other radio if you like)
  • Audio piping between several software
  • Basic operation with OmniRig

Step 1 – Setup SDR-Console and IC-705 with correct frequency

First you need correct frequency for SDR-Console and IC-705. You can download and use the prepared files from this site.
Start SDR-Console and set the downlink (USB) to the satellite you would like to use. Set the IC-705 to the uplink of the satellite, note it has to be LSB-D (LSB with data mode).

Step 2 – Config WSJT-X

Start WSJT-X and config as following:

  • Rig should be Omnirig and your setup for IC-705
  • Mode should be “None” to avoid WSJT-X to set the rig to USB-D
  • Soundcard Input should be the virtual audio from SDR-Console
  • Soundcard Output should be the IC-705 mic

Step 3 – Start Satellite External Radio in SDR-Console

Now start the “Satellite External Radio” in SDR-Console. Select the same OmniRig radio as in WSJT-X. Select the correct uplink frequency and turn on Doppler correction in External Radio.
Now the magic happens! SDR-Console is starting to doppler correct the frequency of the IC-705 and WSJT-X reads the correct frequency from IC-705 in real time!

In this image you can see External Radio and WSJT-X with correct frequency:

Step 4 – Select correct RX frequency in SDR-Console

Select the correct downlink frequency in SDR-Console and enable Tracking in the Satellite Window for the satellite.
Now wait for the satellite to be in your footprint.

Step 5 – Find yourself on the satellite transponder

When the satellite is in your footprint, you need to manually adjust the TX-frequency (at the External Radio window) and RX-frequency, as the SDR-Console software does not have a “tracking RX/TX VFO” function.

  • Find a free area on the satellite transponder
  • Turn your TX output to very low
  • Start transmitting FT4 or use the Tune function in WSJT-X
  • Adjust TX/RX so that your signal is in your RX bandwidth

Step 6 – Start calling CQ

Now you are ready to start calling CQ and making QSOs! Remember – use the minimum TX power, FT4 is very effective. And be sure not to call over a CW or SSB station.

How to use a 2nd instance of WSJT-X for RX of your own FT4 signal

If you would like to check your own FT4 signal (for testing and learning) it is possible to start a 2nd instance of WSJT-X as receiving only.

  • Create a new configuration in WSJT-X where Radio->Rig should be set to None and Audio Input should be the piped audio from SDR-Console.
    Save it to a name of your choice {your_configuration_name}
  • After you have started WSJT-X for the TX (see above) start a 2nd instance with this command in a cmd window:
    {path_to_your_wsjtx}wsjtx.exe –rig-name={your_configuration_name}
  • Now when you TX your FT4 signal the 2nd instance will decode your own signal. See the example below:

Finally, below is a recorded video of a test via satellite AO-73 decoded with a 2nd instance.
If you have any questions about this setup please contact AMSAT-SM (Lars SM0TGU) at

Hardware and "How to..."

Working satellites with IC-705 PstRotator or SDR-Console

This is a guide how to working satellites with the IC-705 or similar rig. When trying to understand the IC-705 I needed to write down how to use it – so this is how this post was born. I will try to explain 3 different user scenarios, each have a case for FM- and linear satellites :

  • Working stand alone (portable) without computer control
  • Working with SDR-Console for doppler adjust and a SDR as receiver
  • Working with PstRotator for doppler adjust

The IC-705 satellite memory examples and file can be found here.
Please contact me if you see anything that will not work in the following user cases – I have limited knowledge.

Setting up PstRotator

I will not explain how to use and set up PstRotator – the PstRotator manual is very good. The settings for Omnirig is like this:

And a typical layout for PstRotator Satellites Tracking is like this (and for reference image for the text below):

Case 1: Using IC-705 stand alone without computer control

FM satellites

  • Select split memory for the satellite in IC-705.
  • If needed adjust the RX frequency with the VFO knob (look at the waterfall).
  • Adjust the TX frequency for doppler when transmitting with VFO knob. Use a printed frequency chart for help.

Linear satellites with SSB transponder
(I have never tried semi-duplex on linear satellites before so not sure if this works)

  • Select split memory for the satellite in IC-705.
  • Adjust the RX frequency with the VFO knob to find a free space on the transponder (look at the waterfall).
  • Adjust the TX frequency (press PTT and use the VFO knob) to the correct frequency on the uplink. Use a printed frequency chart for help.

Case 2: Using IC-705 with SDR-Console v3

In this case the IC-705 is working as the transmitter with full doppler control and a SDR as receiver, also with doppler control.
This is my primary working setup for now!

FM satellites

  • Select the downlink frequency in SDR-Console for your SDR receiver and enable tracking in the satellite window, this will doppler control your RX.
  • Select the uplink memory for the satellite in IC-705 to get correct CCTCS tones.
  • Select the uplink frequency in SDR-Console, it will be transferred to External Radio windows.
  • Start External Radio in SDR Console for doppler control – no need to do anything on the IC-705 – just transmit.

Linear satellites with SSB transponder

  • Select the downlink frequency in SDR-Console for your SDR receiver and enable tracking in the satellite window, this will doppler control your RX.
  • Select the uplink frequency in SDR-Console, it will be transferred to External Radio windows.
  • Adjust the RX frequency at SDR Console to find a free space on the transponder (look at the waterfall).
  • Start External Radio in SDR Console for doppler control.
  • As SDR Console does not link (track) up/downlink VFOs – adjust the TX frequency on the IC-705 with the VFO knob to the correct frequency on the uplink. Doppler is corrected also during TX. Use a printed frequency chart for help.
    You can also adjust the frequency with the mouse wheel in at the External Radio windows. I find this better then using the VFO knob on the radio.

    In late 2021 I have made a virtual VFO control that is working well and this is the way I’m working all my QSOs now.
    Please see this post on my GitHub for more info.

Case 3: Using IC-705 stand-alone with PstRotator

In this case PstRotator sets the correct frequency and mode on the IC-705 and has doppler control for both RX and TX. You are working IC-705 stand-alone as semi-duplex.
Note! I’m not using this setup for now.

FM satellites

  • Select the satellite from PstRotator Favorites. Correct frequency, mode and subtone are now set in IC-705 VFOs.
  • Press the “UP+DN” on PstRotator. Doppler is now adjusted on both RX and TX.
  • No need to do anything on the IC-705 – just transmit and listen.

Linear satellites with SSB transponder

  • Select the satellite from PstRotator Favorites. Correct frequency and mode are now set in IC-705 VFOs.
  • Press the “UP+DN” on PstRotator and check that VFO linking are set to “Reverse”. Doppler is now adjusted on both RX and TX and the VFOs are linked.
  • Adjust the RX frequency with the VFO knob to find a free space on the transponder (look at the waterfall). The TX is linked and will have correct frequency.
  • Change the VFO linking to “Not linked” on PstRotator. This means that both TX and RX are still doppler adjusted but the TX frequency is locked (fixed). If needed you can adjust the RX frequency with the VFO knob on the IC-705.

Finally this is a short video when using the tiny GPD MicroPC with PstRotator and IC-705 as a portable computer controlled doppler adjustment.

Hardware and "How to..."

Satellite Memory File for IC-705

This is a memory group file over satellite frequencies for Icom IC-705 and CS-705 software. It is not complete and will be updated. Feel free to use it, change and add, make your own groups etc.

The memories are used like this:

  • Channels named with satellite name, for exemple “PO-101 Split”, are used in split mode. This channel can be used when using the IC-705 for portable operation or without an extra receiver .
  • The FM-satellites also has five split memories each with AOS-LOS frequencies – for portable operation without computer doppler tuning.
  • Channels named with satellite name and Uplink, for exemple “PO-101 Uplink”, are used only for uplink (not split). This can be used with software like SDR-Console v3 (external radio) or if you have an extra receiver.
  • Channels named with satellite name and Downlink, for exemple “RS-44 Downlink”, are used only for downlink (not split).

Import the memory file into CS-705:
Note! Be sure that you not overwrite anything in your IC-705 when cloning. Make a backup of your current settings!

  • Create a new memory group
  • Mark this new group
  • Choose File->Import->Group and choose the .csv file
  • The memories will now be imported to CS-705
  • Clone to your IC-705

As CS-705 seems to handle character set different between regions I have now created two files. If one does not work, try the other one. Comma separated is working for North America.

Download the latest files from SM0TGUs Github:

The files has to be downloaded as a zip file from GitHub, then use your file of interest:

If you have problems downloading the files from GitHub please contact us and the files can be sent via mail.

RT Systems Memories example

The following explanation is from Jack Spitznagel – KD4IZ, for the RT Systems software.This brief explanation assumes that the RT Systems IC-705 Programmer user knows how to import memories into the software:

  1. Before you merge these into an existing RT Systems memory set, it is first necessary to open the .CSV file in a spreadsheet (Excel or Libre Office) and edit the Channel Number and Bank names. Save the edited file as a .CSV file.
  2. Channel numbers should be set to start numbering at the first open memory row (this example: if row 77 is your first open memory row, start numbering at 77, go up to 99).
  3. Bank numbers should be changed to the first open memory Bank # in the form “##:Bank Name”. In the example, “04:Satellite” was used because Bank 0, 1, 2, and 3 already have assigned names in the memopry file that was used. Interestingly, the “Satellite” Bank Name was not recorded which requires some easy editing of the new file.
  4. Save your RT Systems memory file to a NEW FILENAME so you don’t lose your settings. Users may want to edit the arrangement once the data is imported into the RT Systems IC-705 Programmer.

Users may want to edit the arrangement once the data is imported into the RT Systems IC-705 Programmer.

Download the latest file from SM0TGUs Github:

Hardware and "How to..."

IC-705 doppler correction with SDR-Console

Here a short video of IC-705 Frequency and Doppler control from SDR-Console.
The first part is frequency control with VFO following the radio.
The second part is doppler control from the Satellite External Radio control.

Download the OmniRig config file from:
Be sure to use the correct CI-V hex code in the seetings for IC-705.

Hardware and "How to..."

IC-705 doppler correction with PSTRotator

To setup the new IC-705 for doppler control with PstRotator software you just have to follow these steps:

  • Download the OmniRig file for IC-705 from here
  • Be sure to set up the IC-705 for USB control according to the manual from Icom
  • Follow the guidelines in PstRotator documents for satellite and rig control, choosing IC-705 from OmniRig setup

Here a short video after the setup:

Hardware and "How to..."

Nya transceivers för satellit

Hej, här kommer en liten spaning över gamla och kommande nya riggar för satellit. Den är absolut inte heltäckande och jag har säkert missat en del viktiga händelser.

Om man kollar historiskt i tiden vad gäller tranceivers för att kunna köra satellit på VHF och UHF med full duplex, dvs. sända på ett band samtidigt som man tar emot på ett annat, så har det uteslutande varit stationära riggar som gäller. Dvs. ganska stora och tunga saker som inte lämpar sig så bra att packa ner i ryggsäcken och köra portabelt. Utbudet har såklart varit mindre än rena HF-riggar men det har alltid funnit några alternativ att köpa.

Förra året kom Icom med en ren VHF/UHF-rig mycket lämpad för satellit, Icom IC-9700. Det är en SDR med många funktioner och priset blev därefter. Den bygger av sin meny-struktur på HF-riggen IC-7300 och en del har köpt båda två för att komplettera varandra. Den är även så pass liten att den går att ta med sig portabelt, men med externt batteri såklart.


När det gäller portabla riggar (full-mode) är det framförallt Yaesu men även Icom som har haft ett par varianter. Ofta har det varit HF/VHF/UHF kombinerade riggar utan internt batteri, men små och lätta och fullt användbara att köra portabelt om man tar med sig ett externt batteri. Ingen av dessa har dock haft full duplex (jag har inte räknat med FM-stationer som ibland har full duplex).

I år har en kinesisk tillverkare, Ailunce, presenterat en portabel SDR-tranceiver HS2 med HF/VHF/UHF till ett förväntat pris runt 500 US$ (tull och moms tillkommer). Denna har inte heller något batteri men i övrigt ser den ut att få intressant innehåll.


Det ska vara enkelt att ansluta till dator direkt med USB. Uteffekten anges till max 30W på HF. I övrigt finns det ingen information om VHF/UHF-delarna eller vilka möjligheter det finns för enkel satellittrafik. Det lär knappast bli full duplex. Förväntad release i juli 2020. Mer info här:

Rent portabelt, med inbyggt batteri, är det utan konkurens FT-817(ND) som gäller. Inte heller denna har full duplex men väl inbyggt batteri. Det är fortforarande, efter 20 år, den rig som används mest för portabla satellit-QSO. Många har löst duplex-problemet med att helt enkelt köpa en FT-817ND till!


Under många år har det ryktas om en efterträdare. När FT-818ND kom 2018 var det många som blev besvikna. Det visade sig vara en 817ND men med några nya komponenter. Men det är i grunden exakt samma radio.

Jag har själv en FT-817ND och jag förstår att den för 20 år sedan var unik. Den verkar tåla vad som helst och jag kör den som en HF-rig på digitala mode. Men att hantera denna radio tycker jag nästan är helt omöjligt. Jag har provat att använda den portabelt och lyssna på satellittransponder men blir bara frusterad när jag försöker använda VFOn och se något på displayen. För mig är det helt enkelt inte roligt. Jag är mycket imponerad över de som har lärt sig att använda FT-817ND för att följa en satellitsignal med doppler!

De senaste åren har några kinesiska tillverkare kommit ut med billiga och små SDR-tranceivers på HF, en del med inbyggt batteri, som blivit populära. Kanske är det därför Icom till slut vaknade?

Hösten 2019 presenterades den portabla IC-705 och gensvaret från radioamatörer blev enormt. Detta var uppenbart något som många hade väntat på. IC-705 använder samma display som IC-7300/9700 och har samma menysystem. Det är en SDR-arkitektur som täcker HF/6m/VHF/UHF. Tyvärr så ser vi ingen full duplex på VHF/UHF. Troligtvis hade det blivit för dyrt att implementera och kanske då även blivit en direkt konkurrent till deras egna IC-9700. Det är oklart just nu hur stödet är för satellittrafik tex. om det går att tracka två VFO:er reverserat för att kunna följa sin nerlänk på en transponder. Men, den har inbyggt batteri som enkelt kan bytas och det är en riktig portabel full mode rig.

IC-705 front

Kanske, efter 20 år, kan vi se en rig som kommer bli en ersättare till FT-817ND. Förväntad försäljningsstart är just nu beräknad till juni 2020. Jag har sett ett förväntat pris på ca. 15 000 kr i Sverige.

Mera info finns här:

Och en japansk manual finns nu tillgänglig från denna sida:

IC-705 anslutningar
Lätt att byta batteri